It’s a cornerstone of the billion-dollar anti-bacterial industry: tricolsan, a germ-killing chemical used in hundreds of common products, including toothpaste, toys and an estimated 75% of the anti-bacterial liquid soaps and body washes sold in the U.S.

But after more than 40 years in use, studies are raising concern about its possible effects, such as hormone-related problems or increased risk of infertility. And like many common chemicals, it pre-dates current laws requiring scientific review, so the FDA will study it now and offer findings later this year.